Commit e9338abf authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'Wimplicit-fallthrough-clang-5.14-rc2' of... 

Merge tag 'Wimplicit-fallthrough-clang-5.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux

Pull fallthrough fixes from Gustavo Silva:
 "This fixes many fall-through warnings when building with Clang and
  -Wimplicit-fallthrough, and also enables -Wimplicit-fallthrough for
  Clang, globally.

  It's also important to notice that since we have adopted the use of
  the pseudo-keyword macro fallthrough, we also want to avoid having
  more /* fall through */ comments being introduced. Contrary to GCC,
  Clang doesn't recognize any comments as implicit fall-through markings
  when the -Wimplicit-fallthrough option is enabled.

  So, in order to avoid having more comments being introduced, we use
  the option -Wimplicit-fallthrough=5 for GCC, which similar to Clang,
  will cause a warning in case a code comment is intended to be used as
  a fall-through marking. The patch for Makefile also enforces this.

  We had almost 4,000 of these issues for Clang in the beginning, and
  there might be a couple more out there when building some
  architectures with certain configurations. However, with the recent
  fixes I think we are in good shape and it is now possible to enable
  the warning for Clang"

* tag 'Wimplicit-fallthrough-clang-5.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux: (27 commits)
  Makefile: Enable -Wimplicit-fallthrough for Clang
  powerpc/smp: Fix fall-through warning for Clang
  dmaengine: mpc512x: Fix fall-through warning for Clang
  usb: gadget: fsl_qe_udc: Fix fall-through warning for Clang
  powerpc/powernv: Fix fall-through warning for Clang
  MIPS: Fix unreachable code issue
  MIPS: Fix fall-through warnings for Clang
  ASoC: Mediatek: MT8183: Fix fall-through warning for Clang
  power: supply: Fix fall-through warnings for Clang
  dmaengine: ti: k3-udma: Fix fall-through warning for Clang
  s390: Fix fall-through warnings for Clang
  dmaengine: ipu: Fix fall-through warning for Clang
  iommu/arm-smmu-v3: Fix fall-through warning for Clang
  mmc: jz4740: Fix fall-through warning for Clang
  PCI: Fix fall-through warning for Clang
  scsi: libsas: Fix fall-through warning for Clang
  video: fbdev: Fix fall-through warning for Clang
  math-emu: Fix fall-through warning
  cpufreq: Fix fall-through warning for Clang
  drm/msm: Fix fall-through warning in msm_gem_new_impl()
  ...
parents dd9c7df9 b7eb335e

Makefile

+3 −6
Original line number Diff line number Diff line
@@ -797,12 +797,6 @@ KBUILD_CFLAGS += -Wno-gnu 
# source of a reference will be _MergedGlobals and not on of the whitelisted names.

# See modpost pattern 2

KBUILD_CFLAGS += -mno-global-merge

else



# Warn about unmarked fall-throughs in switch statement.

# Disabled for clang while comment to attribute conversion happens and

# https://github.com/ClangBuiltLinux/linux/issues/636 is discussed.

KBUILD_CFLAGS += $(call cc-option,-Wimplicit-fallthrough,)

endif



# These warnings generated too much noise in a regular build.
@@ -983,6 +977,9 @@ NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include) 
# warn about C99 declaration after statement

KBUILD_CFLAGS += -Wdeclaration-after-statement



# Warn about unmarked fall-throughs in switch statement.

KBUILD_CFLAGS += $(call cc-option,-Wimplicit-fallthrough=5,$(call cc-option,-Wimplicit-fallthrough,))



# Variable Length Arrays (VLAs) should not be used anywhere in the kernel

KBUILD_CFLAGS += -Wvla

arch/mips/include/asm/fpu.h

+1 −1
Original line number Diff line number Diff line
@@ -76,7 +76,7 @@ static inline int __enable_fpu(enum fpu_mode mode) 
		/* we only have a 32-bit FPU */

		return SIGFPE;

#endif

		fallthrough;

		/* fallthrough */

	case FPU_32BIT:

		if (cpu_has_fre) {

			/* clear FRE */

arch/mips/mm/tlbex.c

+2 −0
Original line number Diff line number Diff line
@@ -1383,6 +1383,7 @@ static void build_r4000_tlb_refill_handler(void) 
	switch (boot_cpu_type()) {

	default:

		if (sizeof(long) == 4) {

		fallthrough;

	case CPU_LOONGSON2EF:

		/* Loongson2 ebase is different than r4k, we have more space */

			if ((p - tlb_handler) > 64)
@@ -2169,6 +2170,7 @@ static void build_r4000_tlb_load_handler(void) 
		default:

			if (cpu_has_mips_r2_exec_hazard) {

				uasm_i_ehb(&p);

			fallthrough;



		case CPU_CAVIUM_OCTEON:

		case CPU_CAVIUM_OCTEON_PLUS:

arch/powerpc/platforms/powermac/smp.c

+1 −0
Original line number Diff line number Diff line
@@ -146,6 +146,7 @@ static inline void psurge_clr_ipi(int cpu) 
		switch(psurge_type) {

		case PSURGE_DUAL:

			out_8(psurge_sec_intr, ~0);

			break;

		case PSURGE_NONE:

			break;

		default:

arch/s390/kernel/uprobes.c

+1 −0
Original line number Diff line number Diff line
@@ -126,6 +126,7 @@ int arch_uprobe_exception_notify(struct notifier_block *self, unsigned long val, 
	case DIE_SSTEP:

		if (uprobe_post_sstep_notifier(regs))

			return NOTIFY_STOP;

		break;

	default:

		break;

	}